Canon PowerShot SD450 Digital ELPH / Digital IXUS 55 Review

White Balance

The SD450 has five white balance presets (daylight, cloudy, incandescent, fluorescent, fluorescent H) in addition to the default auto white balance. There is also a 'custom' white balance setting, which allows you to point the camera at a white or gray object and set the white balance manually. The custom white balance setting is remembered even if you turn the camera off. In normal outdoor shooting the auto white balance works perfectly (as confirmed by our studio tests). Indoors it's a bit more hit and miss, as we've seen with most Canon PowerShots, fluorescent lighting doesn't cause much of a problem, whereas incandescent (tungsten) lighting causes a fairly strong orange color cast. Best to stick to the preset (or one-push custom WB) if you want more neutral colors. We've spoken to Canon about their approach to white balance and have been told that the warm colors we see when shooting under incandescent light are intentional and are intended to 'try to keep some of the warm atmosphere of this kind of shot'.

Outdoor - Auto WB
Red -0.5%, Blue -1.1%
Excellent

Fluorescent - Auto WB
Red 0.0%, Blue -0.2%
Excellent

Incandescent - Auto WB
Red 9.6%, Blue -15.5%
Poor

Flash Performance

The SD450's built-in flash has a quoted working range of 0.5m - 3.5m (1.6 - 11.5 ft) at the wide end of the zoom and 0.5m - 2.0m (1.6 - 6.6 ft) at the tele end. It also works down to about 30cm (12 inches) in macro mode (in all cases assuming the ISO is set to auto). In our real-world tests the flash did a fantastic job, exposing perfectly in a wide range of situations and with virtually no color cast. It's also pretty fast - even with the red-eye reduction turned on, meaning you won't miss any spur of the moment shots waiting for the flash. In fact - as long as you remember the range limitations of the flash you'll find this the perfect 'social' snapshot camera. We found the AF illuminator would allow focus in complete darkness (or as near as we can get) at distances of up to around 1.0m. In low light the AF illuminator can help focus at distances of up to around 1.8m.

Skin tone
Excellent color and exposure

Color chart
Excellent color and exposure

Macro Focus

As is common to most compact digital cameras the SD450's macro mode is most effective at the wide end of the zoom, where you can get as close as 3cm - unusually close for an ultra-compact. At the long end of the zoom the performance is less impressive - 30cm subject distance - but still pretty useful. There is inevitably some distortion when shooting very close up at the wide end, but it is not too strong, and certainly less so than many of its competitors.

Barrel and Pincushion Distortion

Barrel distortion is - at 0.7% - very low for a camera in this class, and certainly doesn't mar real world scenic shots. There is no measurable distortion at the telephoto end of the zoom. We did notice a tiny amount of vignetting (darkening of the corners of the frame) at the widest zoom setting, but didn't see this in real world shots. If you look at the full size images you'll also notice that the corners are quite soft, but again this isn't something we found to be a serious issue when shooting in the real world.

Barrel distortion - 0.7% at Wide angle
Equiv. focal length: 35 mm

Pincushion distortion - 0.0% at Telephoto
Equiv. focal length: 105 mm

Specific Image Quality Issues

Of course all ultra-compact cameras such as this are going to present some kind of compromise when it comes to image quality. The question is how much of a compromise are we prepared to accept in image quality terms to get a camera that is truly pocket-sized?

First the good news; this is a Canon and has all the usual Canon trademarks; excellent, vivid but natural color, very accurate exposure and focus and a surprising amount of detail (see resolution tests).

Of course it's not all a bed of roses; the SD450 (like other SD's before it) shows some corner softness at the wide end of the zoom, though it's not strong enough to show in the majority of everyday shots, especially when printed at 'normal' sizes (under 5x7 inches). We found corner softness to be less of a problem than with the SD300 we tested, though this is more likely to be batch variation than a significant difference between the two cameras (which we presume to share the same lens). There is also the usual problem of purple fringing.

Finally, as with pretty much every Canon compact we've tested we found using the clever 9-point AiAF system (which attempts to guess where the subject is in the frame) not only slowed down focusing, but resulted in far more focus errors than the simpler center-focus setting. We would advise turning AiAF off, as we did for this review.

Color fringing

Some purple/blue fringing is present to some degree in all shots containing very bright (especially overexposed) areas, and in some shots it's very pronounced. This is something Canon really needs to sort out.

100% crop

35 mm equiv., F2.8

Burnt out highlights/dynamic range

As with all small sensor compacts the SD450 has some problems with high contrast scenes with a very wide dynamic range. It's no worse than its competitors (this is a sensor issue more than anything else), but to Canon's credit the exposure system seems to do an excellent job of retaining highlight detail most of the time, and the default contrast is not as high as on some competitor models, meaning more fine tonal detail is preserved. Be aware, though, that there are times when the difference between the darkest and lightest parts of a scene will mean that something - usually highlight detail - is going to be lost.